Following this month's intense rainfall in the north of England an Environment Agency alert has highlighted the flood risk to the crumbling nuclear waste dump adjoining Sellafield in Cumbria, writes Marianne Birkby - a dump which remains in use despite its condemnation by the EA in 2005 due to its likely destruction by rising seas. Now it really is time to close the gate on Drigg!

Standing water, sometimes contaminated with low levels of radioactivity, is present in approximately half of the containers at the tops of stacks ... Corrosion, sometimes fully penetrating, is present in some container lids at the tops of stacks.

But there has been little media focus on what this means for nuclear waste buried at Drigg, the UKs 'Low Level Waste Repository', located near the Sellafield nuclear site on the Cumbrian coast.

Yesterday the Environment Agency issued a flood alert for the River Irt which runs alongside the Drigg nuclear dump. The Environment Agency’s flood map illustrates the River Irt inundating the Drigg site on the southward side with floodwater also encroaching from the northward side.

This has not actually happened yet - the map (right) illustrates risk, not actual flooding. But it certainly gives cause for concern as Storm Frank ditches further enormous quantities of rainfall on the Cumbrian mountains and fells.

On the same day, 30th December, Cumbrian campaign group Radiation Free Lakeland sent a letter to Cumbria County Council asking for Drigg's gates to be locked to any more nuclear waste given the dangers from flood waters entering the site, eroding the landfill and contaminating land, river and and sea with radioactive waste.

"To describe the UKs nuclear waste site as a 'Repository' is putting a spin on the UKs main nuclear dump for 'low level' waste", the letter states. "There is controlled discharge direct to the Irish Sea not to mention run off to the Drigg Stream and River Irt.

"Discharges to the air of radioactive gases are ongoing. According to the British Geological Society the Drigg site is above a regional aquifer. It is also likely to be destroyed by coastal erosion in 500 to 5,000 years (computer modelling can be wrong either way). Much of the waste is long lived and high risk."

Even the title of the application is hugely misleading. The date for 'closure' is set at 2079. So Drigg would continue to accept nuclear waste for more than six decades to come.

The site would be 'capped'. Again this is misleading: to 'cap' a nuclear dump is akin to putting a cap on a fizzy lemonade bottle which has holes in the bottom. Despite a 'cap' the site will continue to leach aqueous emissions to groundwater and gaseous emissions to air for as long as the wastes remain dangerous - which in some cases is the half life of the universe.

"The Drigg site uses two disposal systems: 1) An original system operated from 1959 (?) to 1988 comprising a series of parallel trenches excavated into glacial clays, back filled with LLW and covered with an interim water resistant cap. 2) Current disposal of compacted waste placed in steel ISO-freight containers, with void space filled with highly fluid cement based grout. These containers are then disposed of in a series of open concrete vaults.

"Radionuclides with highest activities in the inventory include 3H, 241Pu, 137Cs, 234U and 90Sr, 238U and 232Th."

This represents a cocktail of relatively short-lived, intensely radioactive species such as the tritium, caesium, strontium and plutonium with half lives measured in years and decades, with daughters such as americium 241 that's dangerous for centuries, mixed in with uranium and thorium isotopes with half lives as long as 14 billion years.

Serious degradation already under way

But the waste has been dumped at the site with little or no regard to either short or long term hazards. From 1940 to 1988 chemical and radioactive wastes was simply 'tumble tipped' into trenches.

Now the waste is compacted into steel shipping containers filled with cement. But the containers, stacked up high on the site, are already suffering from serious degradation, with widespread cracking and corrosion, as the LLW management wrote in 2013:

"in containers at the tops of stacks, the external capping grout has undergone extensive physical degradation and settlement; the lids are not full of grout, and the grout is generally heavily cracked. The state of the capping grout in underlying layers is better; most containers only show sparse cracking. Standing water, sometimes contaminated with low levels of radioactivity, is present in approximately half of the containers at the tops of stacks ... Corrosion, sometimes fully penetrating, is present in some container lids at the tops of stacks ..."

In June 2005 the Environment Agency wrote: "BNFL (Now the NDA) has not yet demonstrated that the wider benefits to the UK from continued LLW disposal on this site outweigh the potential future impacts ...

"We have concluded that the 2002 safety cases fail to make an adequate or robust argument forcontinued disposals of LLW because:(i) Estimates of doses and risks from existing disposals to members of the public in the future significantly exceed current regulatory targets.(ii) BNFL indicates that the LLWR is likely to be destroyed by coastal erosion in 500 to 5,000 years.(iii) The 2002 safety cases include insufficient consideration of optimisation andrisk management, to demonstrate that impacts will be as low as reasonablyachievable (ALARA)."

But they have since revised that position and now take a formal view that "the potential for disruption of the site" (by which they refer to inundation by sea and floodwaters) "is an acceptable risk."

Radiation Free Lakeland agrees with the Agency's 2005 findings that that the real and present threat of inundation of the Drigg site - which is only about 300m from the sea and lies just 8 metres above mean sea level - by flood or by sea is not an acceptable risk to the people of Cumbria or to our international neighbours.

"We are concerned by the potential for the destruction of the LLWR by coastal erosion. These concerns appear to be shared by both BNFL and BNFL's peer review panel (Hilland Irvine 2003). Regardless of the calculated risks, the potential for the destruction of the LLWR by coastal erosion means that disposal of long-lived LLW in the LLWR might be creating undue burdens on future generations."

Tell it to the birds

Up until 1958 thousands of black headed gulls eggs from the Drigg and Ravenglass gullery were harvested at a time in basketfuls and sold in London. The black headed gull is now on the amber list. The collapse in the mid 1980s of the largest black-headed gull breeding colony in Europe on the Drigg dunes has never been satisfactorily explained.

The official explanation is that a fox did it: "the concentrations of radionuclides in the foods, body tissues and general environment were at least three orders of magnitude too low to have had any effect. The more likely cause of the desertion of the gullery was the combination of an uncontrolled fox population, the severest outbreak of myxomatosis amongst the rabbits since 1954 and the driest May–July period on record, all in the same year (1984)."

Meanwhile childhood leukemia is officially blamed on 'population mixing' due to the influx of workers firstly to the 1940 explosives factory (Royal Ordnance Factory) at Drigg and then the ROF at Sellafield.

The irony of this incredible argument is that the plan for three new nuclear reactors at 'Moorside' a few miles from Drigg ('Moorside' is at the village of Beckermet) would involve a boom and bust influx of thousands of workers along with a further tsunami of nuclear wastes and ever more Driggs.

And let's not forget the rising sea level problem. The Sellafield site lies within 100m of the sea and most of it is just a few metres above sea level. The nuclear site, already one of the most dangerous and contaminated in Europe, could be inundated by sea water within a century.

Is it really wise to go adding to the problem with a massive complex of three huge new nuclear reactors? When the current problems at the Sellafield / Drigg site have so manifestly not been solved?

Marianne Birkby is spokesperson for Radiation Free Lakeland (RFL). RFL is a voluntary organisation of local activists giving their own time and expertise freely. Any donations go directly to campaigning for nuclear safety.